The Applicant is aware of a process for extracting metal values from metal bearing ores which comprises, in a milling stage, milling wetted ore to produce a slurry; adding a lixiviant to the slurry from the milling stage; passing the slurry to a leaching stage where the lixiviant leaches metal from the ores, with the metal thus being dissolved in the lixiviant; passing the leached slurry to a carbon-in-pulp (`CIP`) absorption section where the slurry is contacted with activated carbon particles which absorb the metal from the lixiviant; separating the carbon particles from the residual slurry; and, in a metal recovery section, recovering the metal from the carbon particles. Instead of the separate leaching and absorption stages, a combined leaching and carbon absorption (`CIL`) stage can be provided.
The slurry from the milling stage is introduced into at least one slurry thickener where the slurry is thickened by removing water therefrom with this water being removed as a thickener overflow water stream. This water can either be returned to the milling stage, or it can be used in a slime dam gold recovery operation, or it can be used for gold recovery from a spent gold ore dump. Such a process is hereinafter also referred to as a `process of the kind described`.